“Be grateful for what you have.” It’s a mantra everyone has no doubt heard before from everyone from mothers and pastors to Oprah Winfrey. Now, science is offering one more reason to count your blessings each night.

John Nezlek, professor of psychology at William & Mary, recently published a pair of papers that prove there’s a relationship between feelings of gratitude and an improved sense of well-being. His studies, published in the Journal ofHappiness Studies and TheJournal of Positive Psychology, are the first to examine the concept of gratitude and its relationship to well-being by measuring how one person varies over the course of several days (called a within-person model). The method allows for the causal relationship between gratitude and other variables, such as well-being, to be determined.

“In both studies we found a positive relationship between people’s sense of gratitude and how they feel about themselves and their lives,” said Nezlek. “We also found that individuals who are asked to think about the things for which they’re grateful were actually able to cope with their stress a little more easily.”

Nezlek’s research is the latest among a handful of studies conducted over the past decade that aim to understand the effects of gratitude on happiness and well-being. Previous studies have linked grateful feelings with lower rates of depression and social anxiety, improved sleep quality and better relationships. Nezlek’s research builds on these by examining the causal relationship between gratitude and well-being as well as considering a broader array of measures for well-being.

His first study, conducted with a group of researchers in Warsaw, Poland, tasked adults in the community to keep a daily log of their levels of well-being, stress, self-esteem, worry and daily gratitude, among other things. In addition, half of the research subjects participated in a gratitude manipulation, in which they were asked to recall and record everything they were grateful for that day.

“As expected, within-person relationships between gratitude and well-being were positive, and our manipulation of gratitude succeeded in reducing people’s reactions to daily stress,” said Nezlek in the study. “Also as expected, our gratitude manipulation had inconsistent effects on mean well-being. Similar to previous research, listing the things for which people felt grateful each day led to greater well-being on some, but not all measures of well-being.”

One explanation is that well-being, in a sense, is a complicated concept.

The second study, which similarly had students at W&M recording their daily levels of gratitude and well-being, examined well-being and its causes more deeply.

“There are two types of well-being – hedonic and eudaimonic,” said Nezlek. “Hedonic is essentially just a measure of life satisfaction – are you happy today? Eudaimonic is not as well understood, but it has to do with understanding life and your place and purpose in the world. They are relatively independent of one another.”

Nezlek’s study – the first to examine the causal relationship between gratitude and eudaimonic well-being – supports their independence. While he found that gratitude on one day was more likely to result in increased measures of hedonic well-being the next day, the same wasn’t true for measures of eudaimonic well-being (which included evaluating how meaningful and purposeful a participant felt their life was each day). Nevertheless, gratitude’s positive impact on hedonic well-being (and, as a result, reduced depression), said Nezlek, is reason enough to remember your blessings.

“I think people need to reflect more on what could have been and what isn’t, but in the positive sense,” he said. “All too often we’re jealous, we compare ourselves to others who have more than we do, and we push for more money and more success. I understand that, but I think we also need to remember that things could be a lot worse. Instead of always wanting more, we need to remember we’re lucky to have what we do have.”